Iris latifolia (English iris)

Native to south-west France and north-west Spain (where it is found in the Pyrenees and Cantabrian Mountains).

Iris latifolia has an ovoid bulb, with fibrous tunics. The stem is 25–50 cm long. The lower leaves are 25–60 cm long, 5–10 mm wide and whitish on the upper surface. The leaves on the stem are narrower. Flowering occurs in late spring and summer. There are usually two flowers (sometimes three), which are deep purplish-blue. The falls are 60–75 mm long and 30–35 mm wide, with a yellow central stripe, with the wide limb tapering into the claw. The upright standards are 40–60 cm long, 15–20 mm wide and oblanceolate (spear-shaped and more pointed towards the base). The fruit is an elongated, beaked, pale brown capsule. The seeds are wrinkled.

Hand-coloured engraving of Iris latifolia (as I. xiphioides) by Sydenham Edwards (1803), taken from Curtis’s Botanical Magazine (Image: RBG Kew)

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Iris latifolia (Image: Martyn Rix)

The British taxonomist John Sims, wrote an article on Iris latifolia (at the time known as I. xiphioides) in Curtis’s Botanical Magazine in 1803, using the common name ‘Pyrenean flag’. Sims explained that the name ‘English Iris’, commonly used by ‘the elder Botanists and even by the modern Florists, was acquired from the plant’s having been first introduced into the Low-Countries from England, most probably without any notice of its true habitat, and hence presumed a native of our country by those that received them; Clusius says, that on his first arrival here in 1571, he sought for it wild, until he was informed by Lobel of its being only cultivated in certain gardens near Bristol, where it had been most probably imported by some vessel from Spain or Portugal. Gerarde [sic] includes it among the British plants…but Parkinson was aware of its real habitat’. Now, centuries later, English iris can indeed be found in the wild in Britain, as a garden escape and in naturalised colonies in grassy places and along roadsides.

There are no known threats to Iris latifolia, which occurs in several National Parks.

English iris is cultivated as an ornamental, for its attractive, deep blue flowers. There are also numerous cultivars with flowers varying in colour from purplish blue (for example Iris latifolia ‘Queen of the Blues’) to white (I. latifolia ‘Mont Blanc’).

Iris latifolia performs well when cultivated in long grass and moist meadow gardens.

Iris latifolia is grown in the Woodland Garden (the area around the Temple of Aeolus) at Kew.

Alcohol-preserved and pressed and dried specimens of other species of Iris are held in Kew’s Herbarium, where they are available to researchers by appointment. The details of some of these, including some images, can be seen online in the Herbarium Catalogue.

Search Kew’s science databases for more information on this species

Kew Science Teams - Monocots I: General Alismatids & Lilioids

Curtis’s Botanical Magazine (Wiley-Blackwell)